• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.61-71
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• 2007

The photosynthetic characteristics and primary production by phytoplankton in open waters of two wetlands (the Banwol and the Donghwa wetland) of Sihwa Constructed Wetland with different water chemistry were investigated to provide the information for the wetland management considering the water treatment efficiency. During the study period (from March to October, 2005) the primary productivity in open waters ranged from 481 to 11,275 mgC $m^{-2}$ $day^{-1}$, which is very high compared with the eutrophic level of 600mgC $m^{-2}$ $day^{-1}$. From the analysis of the photosynthesis-irradiance (P-I) model parameters, the photosynthetic characteristics may be affected by different concentration and ratio of nutrient (N and P) between two wetlands. Assimilation number (AN) was higher in the Donghwa wetland (average AN: 8.5gC $gChl^{-1}$ $hr^{-1}$) with high P and low N/P ratio than the Banwol wetland (average AN: 5.8gC $gChl^{-1}$ $hr^{-1}$) with high N and high N/P ratio. This result indicates that AN may be concerned with phosphorus than nitrogen and low NIP ratio. Positive correlation (R=0.81) was observed between the initial slope and AN, implying that AN was high in case of phytoplankton having more active photosynthesis ability under low light. On the other hand, maximum photosynthesis (Pmax) was related positively with chlorophyll a concentration showing correlation coefficient of 0.47. In this study, considering the high primary production through phytoplankton photosynthesis in open waters of Sihwa Constructed Wetland, the produced organic matter by phytoplankton may affect the water quality within wetland and its efficiency of water treatment. Also, the photosynthetic characteristics may be affected by different nutrient enrichment (especially phosphorus) of wetlands. This study suggests that the production by phytoplankton and its characteristics in open water of constructed wetland for water treatment should be considered to improve the removal efficiency of organic matter.

• Journal of Educational Research in Mathematics
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• v.20 no.3
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• pp.413-444
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• 2010

The purpose of the present study is to develop an instrument of mathematical learning motivation and causal attribution for students and to analyze the results of the instrument. Based on the literature review, mathematical learning motivation is the cumulative effects of self-assessment and self-regulation in mathematical learning and achievement experience. Three factors of mathematical learning motivation is identified as self-regulatory efficacy, task difficulty and mathematical anxiety with 17 self-regulatory efficacy items, 9 task difficulty items and 9 mathematical anxiety items. Three factors of causal attribution for success is identified as ability/effort, luck, and other person with 6 ability/effort items, 4 luck items and 3 other person items. Also, four factors of causal attribution for failure is identified as ability, effort, luck, and other person with 3 ability items, 7 effort items, 3 luck items and 4 other person items. The instrument of mathematical learning motivation and causal attribution for success and failure was administered to 919 middle school students from eight different middle middle schools in Seoul, Gyeonggi-Do, Busan, jeolla-Do area. The correlation of three factors of mathematical learning motivation was calculated. As a result, a positive correlation between self-regulatory efficacy and task difficulty was appeared but mathematical anxiety has a negative correlation with self-regulatory efficacy and task difficulty. This study also examined the differences about mathematical learning motivation's sub-factors shown by three groups of mathematics achievement level. Students of higher achievement level showed that the degree of self-regulatory efficacy and task difficulty was higher than that of lower level group. Students of lowest achievement level showed significantly higher mathematical anxiety degree than that of middle and high group. Students that have higher degree of self-regulatory efficacy and task difficulty preference were attributed into ability/effort cause toward success of mathematics achievement. Also, Male students preferred more difficult task and higher degree of self-regulatory efficacy in mathematics learning than female students. On the contrary, Female students showed higher mathematical anxiety level than male students.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.39-49
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• 1983

By use of three paddy rice lines as the near-isogenic in plant type (Broom, Open, and Spread type in tillering angle), the interspecific competition patterns of rice plants with three important weed species (Cyperus serotinus, Eleocharis kuroguwai, and Potamogeton distinctus) under the three densities of weed standing (0.25 and 50 percent of the rice plants), were observed. Under the experimented conditions, paddy yields were varied more significantly with weed competition descriptions than with plant types of paddy rice. And spread typed rice was more competitive to the detected weed species, however, the broom and spread typed rice were to Potamogeton SP, among others. The result of the clustering analysis of crop-weed competition patterns, estimated by 1-Q mode correlation coefficients, indicated that the first-order component affecting the competition patterns of crop-weed was rather the plant types of rice than either weed species or weed standing densities.

• Korean Journal of Cognitive Science
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• v.11 no.2
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• pp.37-51
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• 2000

The present study compared computer users target-selection response patterns when the targets were varied in terms of their relative location and distance from the current position of the cursor. In Experiment 1, where the mouse was used as an input device, the effects of different directions and distances of simple target(small rectangle) on target-selection response were investigated. The results of Experiment 1 can be summarized as follows: (1) Overshooting was more frequent than either undershooting or correct movement and (2) this tendency was more prominent when the targets were presented in the oblique direction or in farther location from the current cursor position. (3) Although the overshooting and undershooting were more frequent in the oblique direction, the degree of deviation was larger in horizontal and vertical direction. (4) Time spent in moving the mouse rather than that spent in planning, calibrating or clicking was found to be the most critical factor in determining total response time. In Experiment 2, effects of the font size and line-height of the target on target-selection response were compared with regard to two types of input devices(keyboard vs. mouse). The results are as follows: (1) Mouse generally yielded shorter target-selection time than keyboard. but this tendency was reversed when the targets were presented in horizontal and vertical directions. (2) In general, target-selection time was the longest in the condition of font size of 10 and line-height of 100%, and the shortest in the condition of font size of 12 and line-height of 150%. (3) When keyboard was used as the input device, target-selection time was shortest in the 150% line-height condition, whereas in the mouse condition, target-selection time tended to be increased as the line-height increased. which resulted in the significant interaction effect between input device and line-height. Finally, several issues relating to human-computer interaction were discussed based on the results of the present study.

• Journal of Nutrition and Health
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• v.53 no.2
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• pp.215-229
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• 2020

Purpose: This study examines the attitude of South Korean adults toward food aid to North Korea and factors associated with it. Methods: An online survey involving 1,000 adults aged 19-69 years was conducted between September-October 2019. Throughout South Korea, the subjects were proportionally distributed with respect to gender, age, and region, to represent South Korean adults. Results: A total of 44.6% of the respondents agreed (Agreement group), 36.7% disagreed (Disagreement group), and 18.7% neither agreed nor disagreed to food aid to North Korea. Compared to the Disagreement group, the Agreement group had a higher concern of food aid to North Korea and a more positive perception on the effect of it. The Agreement group selected "direct assistance from the government" whereas the Disagreement group chose "support through international organizations" as the most appropriate channel for food aid to North Korea. Logistic regression analysis revealed that South Korean adults showing a more positive perception on the effect of food aid to North Korea were more likely to agree to the aid (odds ratio [OR], 19.32). Moreover, compared to the conservatives, the progressives were more likely to agree to food aid to North Korea (OR, 5.94). South Korean adults in their 40-50s were more likely to agree to food aid to North Korea than those in their 20-30s (OR, 2.81). South Korean adults with a higher concern of food aid to North Korea (OR, 3.93) and a greater positive perception on Korean unification (OR, 1.88) were more likely to agree to food aid to North Korea. Conclusion: The most important factor associated with the attitude of South Korean adults toward food aid to North Korea was their perception on the subsequent effect. As strategies to draw social consensus on food aid to North Korea, we recommend systematizing the monitoring process on the effect of providing food aid to North Korea and informing the public of the outcomes.

• Journal of Bio-Environment Control
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• v.19 no.2
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• pp.88-92
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• 2010

This study was conducted to compare the quality characters of 15 different tomato cultivars ('Dotearang Dia', 'Super Dotearang', 'Super sunroad', 'Hoyong', 'Mirokku', 'Baccuhs', 'Mascara', 'Poseidon', 'Radido', 'Madison', 'Rapsodie', 'Solomon', 'Amaral', 'Picasso', 'Tymaxx') and find out the correlation among the quality characters in order to get basic informations for exporting tomato. The $a^*/b^*$ value of fruit surface showed from 2.8 to 4.8, but there was no significant difference in fruit surface color value, such as $a^*$, $b^*$ and $a^*/b^*$ among the cultivars. The respiration and ethylene production rate also were not shown any significantly difference among cultivars. The firmness of fruit was higher in 'Picasso', 'Tymaxx' and 'Madison' cultivars. The contents of soluble solids was higher in 'Hoyong' and 'Dotearang Dia' cultivars. The vitamin C content was higher in 'Super Sunroad' and 'Dotearang Dia' cultivars. The titratable acidity was higher in 'Hoyong' cultivars. The sugar/acid ratio that depended on soluble contents was lower in 'Amaral', 'Picasso', 'Tymaxx' cultivars that showed lower soluble contents. Conclusionally, The firmness that was one of the most important quality character in exporting tomato was higher in European cultivars, but soluble solide and vitamin C content were higher in Japanese cultivars. The significant correlation coefficient values were determined (more than p = 0.05) between $a^*/b^*$ and other quality characters. The results suggested that surface color was the most suitable character represented tomato qualities. The high coefficient value (r = 0801) between $a^*/b^*$ and the contents of soluble solids. The firmness and the contents of soluble solids that is the most important factor for exporting showed significant negative correlation (r = -0.611).

• 대한공업교육학회지
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• v.39 no.2
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• pp.19-36
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• 2014

The purposes of this study are to grasp industry vocational subject student-teachers' instruction area, compare cognitive level of cooperating teacher and student-teachers for the importance of instruction area and secure base data required to develop educational practical area of professional teachers in specialized high school. To achieve this, instruction area of instruction teacher in charge of industry vocational subject pre-teacher education was developed by document consideration and expert verification and differences of importance cognition for the area was compared between educational practice insturction teacher and student-teacher. The results are as the following. First, for the instruction areas that educational practice instruction teachers should teach student-teacher, there are 7 categories, 17 mid-fields and 85 subsections. Especially expert group suggested an opinion that areas of teacher's values and personality formation should be added to pre-teachers. And, they judged that category of school business showed low validity for educational practice instruction teacher's instruction area. Second, educational practice instruction teacher importantly cognized 'class activity', 'student instruction and class management' and 'development of desirable view of education attitude'. On the other hand, they cognized 'development and management of curriculum', 'support on educational activity', 'industrial-educational cooperation and tie with local community' and 'specialty improvement' less importantly. Student-teachers cognized 'class activity', 'student instruction and class management', 'specialty improvement', 'development of desirable view of education attitude' importantly. They cognized 'development and management of curriculum', 'support on educational activity' and 'industrial-educational cooperation and tie with local community' relatively less importantly. Third, both educational practice instruction teachers and student-teachers importantly cognized 'class activity', 'student instruction and class management' and 'development of desirable view of education attitude'. However, student-teachers importantly cognized, but educational practice instruction teachers didn't importantly cognized 'specialty improvement'. Both two group cognized 'development and management of curriculum', 'support on educational activity' and 'industrial-educational cooperation and tie with local community' less importantly.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.231-238
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• 2006

The physical properties of seven perlites different in particle size distribution were investigated to develop perlite bag culture in Korea. Particle sizes of 1.0-2.8mm and larger than 2.8 mm were rather evenly distributed in S-1 (1.2-5 mm), S-2 (0.15-5 mm) and S-5 (parat No.1). Larger particles were less in S-3 (1-3 mm), S-4 (Parat No.2), S-6 (OTAVI) and S-7 (Agroperl B-3). S-4, S-6 and S-7 contained lots of particles less than 1 mm in size. Total porosity was similar among substrates with the value of $59{\sim}62%$. Container capacity was between 35-40% regardless of substrates except in S-2 with 27.7%. Water content, which was about 60% at 0 kPa, was decreased sharply at 4.90 kPa regardless of substrates, which meant the easily available water was plenty in any kind of perlite tested. Substrates, S-1, S-2 and S-3 with different particle size distribution, were investigated to evaluate for perlite bag culture. Six tomatoes (Licopersicon esculentum Mill. cv. Rokkusanmaru) were planted in a perlite bag of 40 liters with the dimension of 120cm in length and 34cm in width. The amount of nutrient solution supplied and its drainage dependent on daily integrated radiation didn't show any regular trend during the growth. Roots in the bag were distributed evenly in S-1 and S-2 than in S-3. Plant grown in S-1 showed the highest total and marketable yield of 8,628 and 7,759 kg/10a, respectively. The number of small size fruits and malformed fruits were more in S-3. Consequently, S-1 with the particle size distribution of 1.2-5 mm is suggested as desirable substrate for perlite bag culture.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.129-150
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• 1985

The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.652-665
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• 2016

National Competency Standards or NCS is an educational system that emphasizes developing job-related abilities. Therefore it will be an effective solution in training field-oriented work forces if properly applied. However, in the department of social welfare, it is not easy to apply NCS to the curriculum since most academic subjects concerning social welfare focus not on practice but on theory and in addition, most of social welfare departments in junior colleges have an accredited curriculum for the 2nd degree of the social worker qualification. This means it is preposterous if NCS is applied to the curriculum without prior changes in the existing qualification system. So, this paper proposes a draft model to apply NCS to the already-accredited curriculum for the 2nd degree social workers in the junior colleges and details are as follows. Firstly, the competency units will be customized for the existing academic subjects in the curriculum rather than developing new subjects in accordance with NCS competency units. Secondly, some client-related competency units including children, seniors, the disabled are newly developed and then applied to the curriculum, which are crucial for the career development at the junior college level. Thirdly, the competency units are categorized into three types in accordance with the degree of job relevancy - type 1, type 2, type 3. Fourthly, four out of 11 basic job abilities are selected and then developed into academic subjects. Fifthly, all competency units concerning the main job market are regarded as one virtual competency unit and then arranged in the order of type 1s, type 2s and type 3s and then the scope of their study is adjusted to the job abilities required at the main job market.